It depends on which region version of QB Online you need to use.
1. If you need to convert data from QB Desktop 2007 US version to QB Online US version, you will upgrade your data gradually on the trial version for QB Desktop 2011, 2015, and any supported version (i.e 2020-2023). Otherwise you can purchase a 3rd party upgrade service.
2. If you need to convert data from QB Desktop 2007 US version to QB Online non-US version, prepare your new blank QBO account. Then you may have 2 options:
1. Utilize a migration tool (i.e TPExporter for Desktop & TPImporter for Online.